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Dynamic <IMG>



Ron,

Are you sending out the proper header information? Check the error_log of apache.
You might see a "premature end of headers" error.  

I've done graphics on the fly using PHP.  They have a good example
too. Also GD ( http://stein.cshl.org/WWW/software/GD/) for a perl or C based solution has some examples of dynamically generating images.
> 
> Does /cgi-bin/tile need to output something differently than if it were
> simply dumping a PNG to a file? 
> 

Yes, you need to send out the header information (header,blankline) then the image.

print ("Content-type:  image/png\n\n");
...{send image}

David

On Wed, 16 Aug 2000, Ron Peterson wrote:
> I'm trying to generate some PNG's on the fly, and include them in some
> web pages.  The C program I wrote to create them dumps the PNG data
> stream to stdout.  I can dump the output to a file and it looks perfect.
> 
 
> So, no problem, I think.  Rather than point to a file w/ my <img> tag,
> I'll point to the program.  Like <img src="/cgi-bin/tile" alt="blah
> blah" width="512" height="512" border=0>.  Doesn't work.  I've checked
> that ownership and permissions of program are o.k. to be run by Apache.

> I'm confused.  I thought this kind of thing was supposed to work.  No? 
> If this is possible, let me know, and I'll keep hacking.  As long as I
> know I'm not wasting my time...
> 
> -- 
> 
> Ron Peterson
> Systems Manager
> Wallace Floyd Design Group
> 273 Summer Street
> Boston, MA  02210
> 617.350.7400 tel
> 617.350.0051 fax
> rpeterson at wallacefloyd.com
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 .david
 David Lapointe
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